To meet the low latency requirement of FL,
we need to collect data distributed among a huge number
of devices rapidly through wireless communications.
However, with enormous number of devices, conventional
interference-avoiding channel access schemes become infeasible
since they normally result in excessive latency.
To overcome
this challenge,
over-the-air computation is a
promising approach for fast wireless data aggregation via exploiting
the superposition property in a multiple access channel [1]}.
